Process and machine for grinding completed plates of artificial dentures



J. S. MILLER Oct. 2-1 1924.

PROCESS AND MACHINE FOR GRINDING COMPLETED PLATES OF ARTIFICIAL DEN'IURES Filed June 9. 1922 3 Sheets-Sheet 1 IN V EN TOR .443) A TTORNE Y Oct. 21 1924.

J. s. MILLER PROCESS AND MACHINE FOR GRINDING COMPLETED PLATES OF ARTIFICIAL DENTURES' 3 Sheets-Sheet 2 Filed June 9. 1922 INVENT OR Oct. 21. 1924. .l,512,126

J. 5. MILLER PROCESS AND MACHINE FOR GRINDING COMPLETED PLATES OF ARTIFICIAL DENTUREE Filed June 9. L922 3 Sheets-Sheet 5 1N VEN TOR UNITED STATES PATENT OFFlCE.

JAMES S. MILLER, OF TBENTON, NEW JERSEY.

PROCESS AND MACHINE FOR GRINDING COMPLETED PLATES OF ARTIFICIAL DENTURES.

Application filed June 9, 1922.

To all whom it may concern:

7 Be it known that 1, JAMES S. MILLER, a citizen of the United States, residing in Trenton, in thecounty of Mercer and State of New Jersey, have invented a new and useful Process and Machine for Grinding Completed Plates of Artificial Dentures, of which the following is a specification.

My invention relates to a process and a machine for grinding full sets of upper and lower artificialteeth which have been fixed in their final relation, as for example in their respective plates. It has for its object to produce full masticating surfaces to enable an individual to masticate food properly, and (assuming the plates to have been correctly formed to fit the patients mouth) the plates will not be so easily dislodged during the usual or normal mastication of food. I will describe a process embodying my invention, and also a machine embodying new and useful improvements for carrying out my process, and then point out the novel features thereof in claims.

Tn the accompanying drawings, Fig. 1 is a top view of a machine which may be em ployed for carrying out certain of the steps of my process. Fig. 2 is a side elevation of the machine shown in Fig. 1. Fig. 3 is a transverse sectional View taken on the line 33 of Fig. 1. Fig. 4: is a perspective view of one of the carrier plates embodied in the machine of Figs. 1 to 3 and a perspective View of two complete sets of upper and lower teeth mounted in plates and held in their bite relation. Fig. 5 isa perspective view of another carrier plate embodied in the machine of Fig. 1. Similar reference characters designate corresponding parts in all of the figures.

In the practice of my process, the upper and lower teeth, without any grinding, are set up or articulated, and the complete sets of upper and lower teeth are then fastened in the plates by any of the well known methods of which vulcanization is one.

The completed upper and lower plates with their full sets of teeth are then placed in the patients mouth, and the correct bite relation of the patient is taken by any of the methods usually employed. The upper and lower plates are then removed from the patients mouth along with the bite impresuntil the Serial No. 566,962.

sion and reassembled as they were in the patients mouth. The upper plate with its teeth is held in a fixed position, and the lower plate with its teeth is also fired but is moved forwards from its bite position on the upper plate and back again to its bite position, in simulation of the forward and backward motion of the human aw. The bite impression is removed before the movement of the lower plate and its teeth begins. A suitable grinding substance or material is used between the two sets of teeth. The lower plate and its teeth is mounted on a carrier plate or other suitable device, and the carrier plate is yieldingly pressed toward the set of upper teeth so that at all times during the grinding operation the two sets of teeth will be in contact and will, upon the return movement of the lower plate and its set of teeth cause both sets of teeth to assume their original bite relation. This grinding action should be continued until the lower set of teeth can be moved forwards and backwards over the upper set of teeth without being separated, that is to say until the masticating surfaces of both sets of teeth are in perfect occlusal arrangement. After this grinding operation, the two plates with their teeth if desired or necessary, may be turned at an angle and the two sets of teeth further ground by a forward and back movement of the lower plate with its teeth from the bite position and back to the bite position. This grinding may be continued lower set of teeth can be turned laterally across the surfaces of the upper set of teeth, in simulation of the lateral movements of the human jaw, without any separation of the dentures.

If desired, the movement of the lower plate with its teeth, during the grinding operation can be limited to that of the patients lower jaw in the forward and lateral directions. The amount or extent of these movements may be determined by any desired method or means which are well understood in the art.

- In cases where there is and overbite by any patient which it is desired to simulate in the artificial teeth, it may be desirable, after the final bite relation has been obtained, to move the lower plate with its teeth backwards from the bite relation and .7 is being done, the bite C is used. Preferthen return it forward again to the bite relation with the grinding substance or material between the two sets of teeth.

It will be observed in the practice of my process, firstit only has to do with completed upper and lower plates in which the sets of teeth have been fixed in their relative positions so that they cannot be displaced during the grinding operation. Preferably this fixed relation is after the sets of teeth have finally been set or secured in the finished plates. Second-the completed plates must be reassembled to again get the correct bite relation and preferably this is secured when the plates and their sets of teeth are in the patients mouth; and thirdthe upper plate and its teeth are held in a fixed position and the lower plate and its teeth also fixed in the correct bite relation, (which is determined by the bite impression) and then moved from the bite position and back to the bite position in simulation of the forward and backward and lateral movement of the patientsjaw. During the forward and backward or backward and forward movements of the lower plate and its teeth from the bite relation and back again to the bite relation, it is-yieldingly held in engagement with the upper dentures.

The accompanying drawings illustrate a machine for performing certain of the steps of my process.

Referring to the drawings, 1 designates a suitable base. 2 designate what I term carrier plates, and as here shown, the plate 2 is held in a fixed position on the base 1, while the plate 2 is given a reciprocating movement. A, B designate the two dental plates and their full sets of teeth and C designates a bite impression which may be ob tained while the plates A and B are in the patients month. In this position the plates A and l) are placed in the machine, the plate A (being the upper dental plate) being held in a fixed position on the plate 2 by any desired means, but as here shown, these means comprisea plaster D generally usedby den-v tists. The plate B with its teeth is also held on the )late2 b an I desired means for ex- J 7 ample aplaster D The two plates A an d B in being fixed on the plates 2 and 2" by the plaster must be 'maintained in the correct bite relation, and preferably while the ably the teeth of plate B should be yieldingly held against the teeth of plate A, during the grinding operations, and as here shown this is secured by having'the plate 2 fastened to the arm 8. The plate 2 is provided with lugs 2" which separate it from the arm 8 and is fastened to the arm 8 bymeans of screw threaded pins 2 carried by the plate 2 and nuts 2 The pins 2 extend through arcuate seats 2 in the arm 8* which provide for an angular adiustplate 13 is r ciprecatet As shown the plate 2 is provided with lugs 3 and is fastened to a wall 4: which is hinged at et to the base 1. The fastening of the plate 2 to the plate 4 is secured by means of screw threaded pins 3" which pass through arcuate slots 3" in the wall 4 and nuts 3. The arcuate slots provide for an angular adjustment of the plate 2 through degrees. A removable support 5 holds the wall 4 in a fixed vertical position. It is removed from its position by a screw 5 when it is desired to lower the wall 4: on its hinges (see Fig. when the plate A. is to be fixed on the plate 2 bythe plaster D. After the plaster has set the wall a with the plates A, B and the bite O is returned to its vertical position and secured in the support 5. In this positon of the plates A and B, the plaster D is filled in between the plate B and the plate 2. The platesQ, 2 are provided with central openings through which the plasters D, D extend so that they may be fixed on their respective plates.

The plate 2" may be reciprocated in'any desired manner, and as here shown, this is secured by means of crank arm 10 carried by a shaft 10 which is rotated from a driving pulley 11. centric 10 with a plate 12 which is mounted to move back and forthon guides 11*, l, mounted on the framework 1. The arm 8 of the hinge 8 isfixed to the plate 12.

E designates a removable and flexible wall or enclosure which as shown in the drawings fits'about the teeth of the two plates A confining the grinding mixture between the two sets of teeth duringthe grinding operas tion.

place by.

A link 11 connects the ec and B and is for the, purpose of" The operation of the machine just deward from its bite position and return it to" its bite position. Care should also be taken that the extent of such movement should be that of the movement of the lower jaw of the patient, and for that purpose an adjustable connection comprising a screw 11* and openings 10 -is provided between the arm 11 and the crank 10. In this position of the carrier plate 2 and with the two plates A andlfi fixed to their carrier plates as before described, the bite impression, C is removed, the flexible closure E placed about the teeth and a suitable grinding material supplied between the teeth. After this is done, the

from the bite relation forward and back to the bite relation until the grinding material has their co-operating masticating surfacesfitted to one another so that the teeth of plate B can be moved back and forth over the teeth of plate A without any separation. It is to be noted that this operation of the machine simulates the for: ward and backward movements of the human jaw in biting and masticating. After this has been done the plates A and B may be turned to any desired angle with the arc of 90 degrees but still in the bite relation and the plate B again reciprocated with the grinding substance between the two sets of teeth from the bite relation and baclrto the bite relation to an extent equal to the lateral movement of the patient. This operation is continued until the masticating surfaces of the bicuspids and molars can move over each other without hindrance in performing the working bite. It is to be noted that in this operation of the machine, it simulates the lateral movements of the jaw in mastication.

Having thus described my invention, what I claim as new is:

1. The process of grinding full sets of artificial teeth which are permanently fixed in the upper and lower dental plates, which consists first in fixing the bite relation of the upper and lower sets of teeth to correspond with the patients bite; holding the upper plate and teeth in a. fixed position and positively moving the lower plate and teeth relatively thereto from the bite relation and back to the bite relation in simulation of the forward and back movements of the human aw with a grinding substance between the sets of teeth, and finally moving the two plates with their teeth to a new position in an arc. of 90 degrees, and again moving the lower plate and teeth relatively to the upper plate and teeth with a grinding substance between the sets of teeth.

2. The process of grinding full sets of artificial teeth which are permanently fixed in upper and lower dental plates, fixing the bite relation of the upper and lower sets of teeth to correspond with the patients bite; holding the upper plate and teeth in fixed position and positively moving the lower plate and teeth relatively thereto from the biterelation and back to the bite relation in simulation of the movements of the human jaw in mastication, with a grinding substance between the sets of teeth until the surfaces are in occlusal arrangement.

3. The process of grinding full sets of artificial teeth which are permanently fixed in upper and lower dental plates, fixing the bite relation of the upper and lower sets of teeth in the patients mouth; holding the upper plate and teeth in fixed position and positively moving the lower plate and teeth rela tively thereto from the bite relation forward and back to the bite relation in simulation of the'movements of the human jaw in mastication with a grinding substance between the sets of teeth until the surfaces are in occlusal arrangement.

4. The process of grinding full sets of artificial teeth which are permanently fixed in upper and lower dental plates; fixing the bite relation. between the two sets of teeth in a patients mouth; holding the upper plate and teeth in a fixed position; holding the lower plate and teeth in yielding engagement therewith and positively moving the lower plate and teeth relatively to the upper teeth from the bite relation and back to the bite relation with a grinding substance between the sets of teeth until the masticating surfaces are in occlusal arrangement.

5. In a machine for grinding full sets of artificial teeth which are fixed in upper and lower dental plates; the combination of a carrier plate for holding the upper set of teeth-in a fixed position; a second carrier plate for holding the lower set of teeth; meansfor holding the two dental plates in correct bite relation of the patient for whom the teeth are intended; and means for moving the lower set of teeth relatively to the upper 'set of teeth from the bite relation forward and back'to the bite relation.

6. In a machine for grinding full sets of artificial teeth which are fixed in upper and lower dental plates; the combination of a carrier plate for holding the upper set of teeth in a fixed position; a second carrier plate for holding the lower set of teeth: means for holding the two dental plates in correct bite relation of the patient for whom the teeth are intended; means for moving the lower set of teeth relatively to the upper set of teeth from the bite relation forward and back to the bite relation; and means for yieldingly holding the lower set of teeth against the upper set of teeth.

7 In a machine for grinding full sets of artificial teeth which are fixed in upper and lower dental plates; the combination of a carrier plate for holding the upper set of teeth in a fixed position; a second carrier plate for holding the lower set of teeth; means for holding the two dental plates in correct. bite relation; means for moving the lower set of teeth relatively to the upper set of teeth from the bite relation forward and back to the bite relation; and a closure surrounding the sets of teeth for confining a grinding substance.

8. In the process of finishing sets of artificial teeth which have been permanently set in plates, the steps of ascertaining the bite relation of the teeth when in position in the patients mouth, attaching the plates in such bite relation to relatively movable mem bers and grinding the teeth by causing such members to move-in simulation of the move ment of the patients jaw in mastication from and back to the bite position with an abrasive substance between the sets of teeth.

9. A process as defined in claim 1 in which the relative grinding movement of the sets of teeth is carried on successively in at least two relative directions.

10. The process as defined in claim 1 in which the abrasive substance is caused to enter between the sets of teeth by surrounding the teeth with a mass of an abrasive substance in fluid condition so that the abrasive substance is carried between the teeth by capillary action.

11. In the process of finishing sets of artificial teeth which have been permanently set in plates, the steps of ascertaining the bite relation of the teeth when in position in the patients mouth and ascertaining the normal movement of the patients jawduring mastication, attaching the plates in such bite relation to relatively movable members, putting an abrasive substance be tween the sets of teeth and grinding the teeth by causing said relatively movable members to move in simulation of the movements of the patients jaw in mastication, and limit ing the extent of such movement to conform with the normal movement of the particular patient, such grinding movement being from and back to the bite position of the particular patient.

12. In a machine for grinding full sets of artificial teeth which are permanently fixed in'upper and lower dental plates, the combination of a carrier plate for holding the upper set of teeth in a fixed position, a second carrier plate for holding the lower set of teeth; means for holding the two dental plates in the bite relation of the patient for whom the teeth are intended; means for moving the lower set of teeth relatively to the upper set of teeth from the bite relation forward and back to the bite relation; means for yieldingly holding the lower set of teeth against. the upper set of teeth; and adjustable means for limiting the movement of the lower plate to that of the lower jaw of the patient.

13. In a machine for grinding complete sets of artificial dentures, the combination of two carrier plates; means for fixing the upper and lower dentures in a vertical plane on said plates in the correct bite relation of the patient comprising material having an impression of the patients bite which is removed from between the dentures after they are fixed on the carrier plates; means for moving the lower set of dentures from the bite relation and back to'the bite relation; and a grinding-substance between said dentures when the relative movement is oc curring.

14. In a machine for grinding complete sets of artificial dentures, the combination of two carrier plates; means for fixing the upper and lower dentures in a Vertical plane on said plates in the correct bite relation of the patient comprising material having an impression of the patients bite which is removed from between the dentures after they are fixed on the carrier plates; means for holding the lower set of dentures against the upper set of dentures; means for moving the lower set of dentures from the bite relation and back to the bite relation; and a grinding substance between said dentures when the relative movement is occurring.

JAMES s. MILLER.

Witnesses: V

CATHARINE C. HoRNYAK, J AS. S. TURF; 

